はじめて、InitialContext? が、なんで "Initial" なのか分かったわ
package com.mycompany.sampleweb; import java.io.IOException; import java.io.PrintWriter; import java.util.Enumeration; import java.util.logging.Level; import java.util.logging.Logger; import javax.naming.Binding; import javax.naming.Context; import javax.naming.InitialContext; import javax.naming.NamingEnumeration; import javax.naming.NamingException; import javax.naming.RefAddr; import javax.naming.Reference; import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; @WebServlet(name = "NewServlet", urlPatterns = {"/NewServlet"}) public class NewServlet extends HttpServlet { /** * Processes requests for both HTTP <code>GET</code> and <code>POST</code> * methods. * * @param request servlet request * @param response servlet response * @throws ServletException if a servlet-specific error occurs * @throws IOException if an I/O error occurs */ protected void processRequest(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { response.setContentType("text/html;charset=UTF-8"); try (PrintWriter out = response.getWriter()) { out.println("<!DOCTYPE html>"); out.println("<html>"); out.println("<head>"); out.println("<title>Servlet NewServlet</title>"); out.println("</head>"); out.println("<body>"); out.println("<h1>Servlet NewServlet at " + request.getContextPath() + "</h1>"); out.println(dumpJndi("", new InitialContext())); out.println("</body>"); out.println("</html>"); } catch (Exception ex) { Logger.getLogger(NewServlet.class.getName()).log(Level.SEVERE, null, ex); } } private String dumpJndi(String prefix, Context ctx) throws NamingException { StringBuilder sb = new StringBuilder(); sb.append("<ul>"); NamingEnumeration<Binding> bindings = ctx.listBindings(""); while(bindings.hasMoreElements()) { Binding binding = bindings.next(); String name = binding.getName(); Object obj = binding.getObject(); sb.append("<li>") .append(prefix) .append(binding.getName()) .append("<font size=2 color='gray'> ") .append(binding.getClassName()) .append("</font>"); if (obj instanceof Context) { sb.append(dumpJndi(prefix + name + "/", (Context)obj)); } else if (obj instanceof Reference) { sb.append(dumpReference(prefix + name + "/", (Reference)obj)); } sb.append("</li>"); } sb.append("</ul>"); return sb.toString(); } private String dumpReference(final String prefix, final Reference ref) { StringBuilder sb = new StringBuilder(); sb.append("<ul>"); Enumeration<RefAddr> refAddrs = ref.getAll(); while(refAddrs.hasMoreElements()) { RefAddr refAddr = refAddrs.nextElement(); String type = refAddr.getType(); Object content = refAddr.getContent(); sb.append("<li>") .append(type).append("=").append(content) .append("</li>"); } sb.append("</ul>"); return sb.toString(); } // <editor-fold defaultstate="collapsed" desc="HttpServlet methods. Click on the + sign on the left to edit the code."> /** * Handles the HTTP <code>GET</code> method. * * @param request servlet request * @param response servlet response * @throws ServletException if a servlet-specific error occurs * @throws IOException if an I/O error occurs */ @Override protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { processRequest(request, response); } /** * Handles the HTTP <code>POST</code> method. * * @param request servlet request * @param response servlet response * @throws ServletException if a servlet-specific error occurs * @throws IOException if an I/O error occurs */ @Override protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { processRequest(request, response); } /** * Returns a short description of the servlet. * * @return a String containing servlet description */ @Override public String getServletInfo() { return "Short description"; }// </editor-fold> }